A Thought Experiment: Vaccines for Personality Traits

Posted by Sappho on May 9th, 2014 filed in Sexuality, Vaccinations


Imagine a world in which homophobia is the lingering effect of a pathogen. Perhaps someday we’ll develop a vaccine for it! This might appeal, if you’re on the side of the culture divide that yearns for an end to homophobia. It might make your skin crawl, if you’re on the side of the culture divide that considers your “homophobia” to be strong moral values.

There are obvious things to say about the “gay germ” theory: That germs are icky, that many people (still) find homosexuality icky, and that a “gay germ” is bound to appeal more, and, if it were in fact real, to reinforce the attitudes of, those who find homosexuality icky, and who are willing to believe other icky things about gay people (such as suspecting gay men in general of being pedophiles), than to people who are gay or gay friendly. But I can’t think of any particularly new or compelling way to talk about those things, so I’m more interested in the implications of a hypothetical world in which a vaccine could prevent homosexuality.

It’s not that a “gay germ” would necessarily mean for an easier path to preventing homosexuality (should prevention be your desire) than another cause. Some pathogens mutate frequently, and are hard to vaccinate against once and for all. Think flu, for which we need a vaccine every year (and one that’s still much less effective than, say, the vaccines for measles or polio). Or, worse, think HIV, for which we haven’t yet been able to bring a vaccine to market, despite decades of trying.

Conversely, we have prevention for some things that aren’t caused by pathogens at all. One of my mother’s cousins suffered such brain damage that she was like an infant for life, because she was an Rh positive baby born to an Rh negative mother. These days, a Rhogam shot in cases of Rh incompatibility prevents Rh incompatible pregnancies from sensitizing a mother, so that she no longer produces antibodies in the case of subsequent pregnancies. One could imagine a similar shot that could be given to prevent the “older brother” effect that makes homosexuality more common in younger brothers.

And even genetic doesn’t always mean unchangeable. Diabetes has a large genetic component, and is manageable with insulin. One could imagine some future in Big Pharma has a medicine that shifts which gender’s pheromones you respond to, or something. One could even imagine a future in which gene therapy replaces the gay gene with a straight gene.

And, no matter what the cause, we can still decide that “Sing if you’re glad to be gay, sing if you’re happy that way” is a more fitting response to our differences than a search for a prevention or cure.

But there’s something special about the “gay germ” theory. To explain what, I’ll return to that passage I quoted from Chris at The Lure:

The hypothetical gay germ violates all of these principles. Rather than maximize its short-term viability, its plan seems to be:

1. Burrow down into the inner portion of the brain, probably the hardest place for an external pathogen to reach
2. Infect a small batch of neurons that control sexual orientation (but little, if anything, else), which, if the germs hits shortly after birth, will have no effect on the host’s behavior for at least a decade
3. ?????
4. Profit!

That’s what life looks like for a targeted gay germ, one that simply shifts our sexual orientation without doing much else. Now, there’s an obvious alternative to a targeted gay germ, and that’s a not so targeted gay germ, one that causes enough general mayhem that its “gay germ” effect is purely incidental to its other activity. Chris, in the comments to his post, responds to a suggestion about that kind of gay germ, and finds it even more implausible than the targeted version:

I will agree that I did not address the issue of the incidental, rather than targeted, gay pathogen, because I regarded that option as even more ludicrous than the alternative. Here are two of but many of the reasons why:

First, think of the numbers involved. As Cochran himself notes, we are not dealing with a handful of isolated cases here, but ~5% of the population. Cochran seems to find that proportion problematic for a genetic cause for homosexuality (it’s not), but it is considerably more problematic for the incidental gay germ. If I understand you correctly, you are arguing that there is a disease currently in the population that is so pervasive and inflicts sufficient undirected brain damage that, in 5% of the population (note, not infected, but the population), a certain cluster of neurons is destroyed. If this were true, the incidental gayness should be the least of our concern. This disease at very least should be knocking out the elements of the hypothalamus that control hunger, hormones, and body temperature in roughly similar proportions of the population. I have no idea what you are doing here in the comment thread of a blog when there is an undetected, likely fatal disease on the loose which only you are aware of. Forget WordPress, alert the CDC.

This points to another problem with the incidental gay germ: sufferers should be expected to have a greater proportion of neurological or at least hypothalamal disorders than the general population. Consider a situation in which homosexuality is caused by a severe infection/fever in early development that causes brain damage including the destruction of the putative “sexual orientation” cluster. One would expect that those who went through such an experience would be more likely than the average person to have other portions of the brain similarly knocked out. Thus, gays should have a greater incidence of hormonal control problems, for instance, or perhaps be more likely to experience mental retardation more generally. Unfortunately, there is no evidence at all to corroborate that supposition and a lot of evidence to suggest that this is not the case….

I agree with Chris that an incidental gay germ sounds improbable, for just the reasons he gives. But it also raises, for me, another thought. Given the lack of payoff for a targeted gay germ, and the amount of other havoc that an incidental gay germ would have to cause, if, by some fluke, I’m wrong, and a gay germ does exist, chances are good that we already know about it, and are probably already working on a vaccine. Sure, we haven’t noticed that it makes people gay. But we’ve noticed one or another of its other effects, and we don’t like it, and we’re ready to do combat.

It’s the nature of pathogens, at least pathogens that mess with our brains in the way a gay germ would have to, that they do things to us that we don’t like, and that we get our medical research in gear to come up with a cure or a vaccine. That means that a world with a gay germ would be a world in which we might, for practical purposes, eliminate homosexuality purely by accident, on the way to eliminating something else.

To illustrate what a world might feel like, in which personality or behavioral traits can be altered incidentally by vaccines, that aren’t perceived as disordered by the people who actually have them, let me propose another hypothetical germ. This will be a thought experiment germ, not one that I think is at all likely to exist, but I will tell you its story, and flesh out how it works and how it comes to an end.

Jayman, the blogger who was my path to Greg Cochran’s “gay germ” theory, has another theory that he likes to promote. This one comes from a blogger known as HBDChick, who believes that some ethnic groups are genetically predisposed to be more clannish than others. Within Europe, for instance, by HBDChick’s reckoning Greeks would be more clannish and English less so (I pick Greeks and English because that’s largely what mix I am). She has a theory about why this would be so, which I (and for that matter Razib Khan) disbelieve, and which I may talk about more seriously in another post (but probably not till after I’ve gone back to Jonathan Haidt blogging for a while).

For now, though, I want, in an entirely unserious way, to propose a thought experiment in which HBDChick is right that some ethnic groups are predisposed to be more clannish than others, but wrong about the reason. In my hypothetical, there is an anti-clannishness germ. Our natural state is to be somewhat selfish and somewhat kin altruistic. What evolutionary benefit can we get from being altruistic toward non-kin? But, for those of us who have survived infection by the “anti-clannishness germ,” our kin altruism behaviors get redirected toward a larger group. The germ benefits, because anti-clannish people are more readily able to relocate to new neighborhoods, where they form new social networks and spread the germ. Anti-clannish people may subjectively feel that they benefit, as they learn to appreciate their more civic-minded cultural institutions, and feel glad of their lower rates of nepotism than those found among more clannish people. Meanwhile, some groups, having different immune genes (immune system genes, you may recall if you read my earlier blogging about Cavalli-Sforza’s Genes, Peoples, and Languages, are among the most variable genes, as you move from one human population to another), and so develop more clannish cultures than the more heavily infected peoples.

But the anti-clannishness germ proves to have a few other effects that are generally disliked. Perhaps it causes fever. Perhaps it’s deadly to particularly vulnerable people, like the elderly, or newborns, or those who are immune compromised. So eventually we develop a vaccine. An ad campaign promotes the new vaccine. Soon it is required for school entrance. And one day, elderly people from the day when the anti-clannishness germ swept the population watch mystified as the younger generation has big fat WASP weddings, avoids moving far from home for college, and generally shows far more kin altruism and far less generalized civic-mindedness than there elders. What are we going to do about The Other Generation?

Obviously, if we did live in such a world, I’d want to know about it. But I can’t deny I’m glad to be able to conclude that we don’t. Vaccines are one of the biggest public health boons ever. Where whooping cough used to kill and polio to cripple, vaccines save us. And suspicion of vaccines is a real public health problem, whether it’s from the Muslim cleric who have at times thwarted polio eradication in Nigeria, or whether it’s the anti-vaccination movement that has brought measles back to the US. I’d hate to live in a world where vaccines altered personality traits in unexpected ways, because it was a world where diseases normally left behind random personality alterations that were seen as benign by the people who had them, but that were really pathogen-produced.

Fortunately, there’s no reason to believe that I do live in that world.



6 Responses to “A Thought Experiment: Vaccines for Personality Traits”

  1. JayMan Says:

    I guess you’re uninterested in rational discourse, because there’s a response from me to your previous post that sits waiting for your approval. Thanks.

  2. Sappho Says:

    Just approved that comment, was away from the blog for a couple of days.

  3. misdreavus Says:

    Your friend, it seems, lacks even a rudimentary understanding of the fundamentals of immunology.

    It’s hardly unusual for an autoimmune reaction to target a miniscule cluster of cells in the body, because that’s exactly what the immune system is for – distinguishing between fine biomolecular patterns between cells, tissues, and sub tissues that are otherwise invisible to even the most gifted among histologists. GUESS what might trigger such a reaction in 5% of the population? A pathogen! You can have homosexuality without significant brain damage everywhere else.

    We have ample evidence now that Type I diabetes (which, again, results from the immune system targeting tiny *clusters* of cells in the Islets of Langerhans) is pathogenic in origin, and narcolepsy (which results from site-specific damage to a nucleus in the hypothalamus that generates the neurohormone hypocretin) has recently been confirmed to be an autoimmune disorder. A pathogen is just perfect for this job. The immune system isn’t going to screw up like this in 2-4% of the male population for no good reason, and the twin studies prove that the overwhelming source of homosexuality is environmental in origin.

    As for whether or not we have identified a specific pathogen responsible for diabetes (or homosexuality), who cares? Theory indicates that such a thing must exist, just like how Pluto was first identified through aberrations in the orbit of Uranus, long before anyone had found it with a telescope. That’s exactly how science works. You could save a lot of time by refusing to waste your effort on hypotheses that are discordant with all the evidence on the table (e.g. “gay genes” or sexually antagonistic selection).

    We’ve also identified the anatomic brain difference that is most likely responsible for obligate male homosexuality in domesticated rams (please Google Charles Roselli’s research, if you ever get the chance) – again, it’s nothing but a sexually dimorphic nucleus in the hypothalamus, one that ostensibly regulates the sex drive. Simon LeVay has identified an analogous difference through histological analysis of the hypothalami of gay and straight men. Whatever the hell it is, it ain’t genetics – although genes are most certain part of the chain of causation that leads to male homosexuality, they are not the sine qua non of “alternative” sexual expression.

  4. misdreavus Says:

    As for whether or not gay men are more likely to suffer from various mental disorders, compared to the rest of the population — absolutely they are. But even if they weren’t, that would hardly contradict the gay germ theory.

  5. Frau Katze Says:

    I may be wrong, but I do not think HBD chick’s theorizes that degree of clannish-ness is genetic. Clearly a tendency to it is innate, but social factors (like the Catholic Church outlawing cousin marriage) are responsible for its absence in much of Europe.

    Given enough social disorder it might return. You never know.

  6. Sappho Says:

    I meant, when I wrote this, to do a post soon after that discussed HBDchick’s argument about clannishness a little more seriously; it involves a proposed interaction between genetic and social factors that, while I found it unpersuasive, failed to persuade me in a more interesting way than most of what I read in the HBDosphere, and it connects with another, not so genetic, topic that interests me (the question of proposed factors related to clientelism, on which I want to say some not at all genetic things at some point). But a conference intervened, and I want to blog about those workshops while they’re fresh, and I’m still blogging my way through Haidt’s book. I probably will combine the serious account of what I make of HBDchick with a post about Nicholas Wade’s book, since the two of them, in different ways, are both arguing for an innate difference in circle of trust where the selective pressure is produced by culture, and so a reaction to them raises some of the same issues.. Also, putting them side by side fits with things I’ve been wondering about where the line falls between HBD as its own little world and what I think of as “crossover” HBD (popular books like A Dangerous Inheritance, or The Bell Curve, that lead to little bursts of more mainstream discussion). And why, for instance, a book like A Dangerous Inheritance may appeal more to someone like Ross Douthat than some of the other stuff (but still only to the point where he’s willing to endorse the first half).

    But there’s so much other random stuff to write and do, so don’t hold your breath for me to actually write that post. Probably a lot of people will have quit reading by then, but that’s OK; this is just a small personal blog anyway.

    As far as clannishness, sure, it could return given enough social disorder. I’m reminded of a post-apocalypse speculative fiction short story that involved a return of nomadism.